1. Field of the Invention
This invention relates generally to the alignment of the front, or steering, wheels of a motor vehicle, and particularly to a radius turntable gauge for facilitating such front end alignment of motor vehicles.
2. Description of the Prior Art
Various devices have been proposed for the straightening of frames, the correction of misalignment and for accomplishing the checking of such straightening work as it is in progress, but generally these known devices are large, heavy, and require substantial space, with the result that they are not convenient for use for quickly checking the alignment to determine the accuracy of the work being conducted.
U.S. Pat. No. 2,250,742, issued July 29, 1941, to C. C. Bennett, discloses a chassis analyzer employing a radius turntable gauge and which is of generally light weight and compact construction. Additional examples of radius gauges intended for use in the alignment of front ends of automobiles can be found in U.S. Pat. Nos: 2,125,534, issued Aug. 2, 1939, to H. Wochner; 2,155,541, issued Apr. 25, 1939, to G. M. Graham, et al.; 2,736,104, issued Feb. 28, 1956, to W. T. Sherman; and 3,181,248, issued May 4, 1965, to M. C. Manlove. None of these known turntables, however, are suitable for use with frame and body straightening equipment of the type employing a fixed, continuous track within which the vehicle is disposed so as to be acted upon by pulling equipment anchored on the track. This type of equipment, which is becoming increasingly popular in the body and frame straighteneing industry, creates special problems as regards the alignment of the front end of a vehicle being repaired.
Many radius turntable gauges are employed which are sunken into a floor or other supporting surface in which alignments are to be conducted. A serious problem encountered with such gauges is that they tend to collect dirt and debris, and eventually become so gummed-up as to become bothersome and unreliable in operation. Thus, maintenance with these known units is very high. While those turntables disclosed in the prior patents cited above are generally disposed above the surface supporting the turntable gauge, these units are generally constructed in a rigid manner which creates levelling and other operational problems.
U.S. Pat. No. 3,135,052, issued June 2, 1964, to C. W. MacMillan, discloses wheel alignment apparatus employing a pair of turntables, wheel-hub mounted camber caster gauges, and a toe-in gauge rod assembly, all of which elements cooperate with one another to check the alignment of the front end of a motor vehicle. The turntable and associated toe-in gauge assembly according to the present invention are intended to be employed with camber and caster gauges in a manner similar to the arrangement of elements as seen in U.S. Pat. No. 3,135,052.